Improvement in millstone-picks



UNITED STATES PATENT OFFICE.

A. S. JONES, OF JOLIET, ILLINOIS.

IMPROVEMENT IN4 MILLSTONE-PICKS.

Specification forming part of Letters Patent No. 34,966, dated April 15, 1862.

To all whom it may concern;

Be it known that I, A. S. JONES, of Joliet, in the county of Till and State of Illinois, have invented a new and improved Millstone- Pick; and I do hereby declare that the following is a full, clear, and exact description of the same, reference being had to the accompanyin g drawings, making a partof this specification, in which-- Figure l is an external view of my invention; Fig. 2, an end view of the same; Fig. 3, a section of the same, taken in the line 0c, Fig. 2.

Similar letters of reference indicate corresponding parts inl theV several figures.

This invention relates to an improvement in that class of millstone-picks in which adjustable cutters are insertedin heads Orhandles.

The object of the invention is to obtain a head or handle which will admit of very thin cutters being employed and securely fastened in position, as hereinafter fully shown and described, whereby the pick may be kept in perfect workingforder with very little trouble, and it is believed a far more durable and economical implement obtained for the purpose than any hitherto constructed.

To enable those skilled in the art to fully understand and construct my invention, I will proceed to describe it.

A represents a wooden handle, which may be of any suitable length, and B is a metal head or bar, which is permanently attached to the handle A, and may be described as be ing formed of two projecting lips da, slightly inclined in an inward direction from their inner ends outward, as shown in Figs. l and The lips a d have a flat outer surface, and each is provided with a series of recesses b, the back parts of which are at right angles with the upper surfaces of the lips. (See Fig. 3.)

C is a metal strap, which is iirmly secured to the outer end of the handle A, and pro jects some distance above the center of the head I3, as shown in Figs. l and 3. In the outer end of the strap C there is fitted a thumbscrew I). This screw passes through the strap C and bears upon the center of a spring-E, the sides of which at its center are notched or provided with recesses c c, into which the sides d d of the strap fit to form guides for the spring` E, the latter being allowed to rise and fall freely in the strap. The spring E is formed of a fiat steel plate bent so that its ends or outer parts e e, each side of a horizontal part f, which is in the strap, will be inclined similarly to the lips d a ofthe headI-i. (See Figs. l and 3.) rlhe parts e e of the spring are of taper form and are equal in length to the lips a c of the head B.

F F represent cutters, which are formed of two thin plates of steel of equal thickness. The front or cutting edges of these cutters are brought to a cutting-edge by two basils g g, one at each side, and the cutters at theirback ends are swaged,so as to form a projection 7i, corresponding in form to the recesses I) in the upper surfaces of the lips ce a, as shown clearly in Fig. 3.

The implement is used as follows: The cutters F F are placed between the parts e e of the spring E and the lips d a of the head B, the projections h at the back ends of the cutters fitting in the back recessesb in the outer surfaces of the lips ct a of the head B. The spring E is then, by means of the screw I), forced inward, so that its outer parts e e will press firmly 011 the cutters F F and retain the same in proper position. In consequence of the projections 7L of the cutters fitting in the recesses Z) the cutters are prevented from being forced back between the parts c e of the spring and the lips a a of the head B under the force or concussion of the blows of the cutters on the stone, and the parts e e of the spring do not require to be pressed upon the cutters F sufficiently hard to break them-a contingen cy which would be liable to occur were the spring E solely relied upon to retain the cutters in proper position.

The cutters E, in consequence of being thin, may be readily ground when dull, and as they become worn by use and shortened their projections 7L are tted in the outer recesses b. The cutters may therefore be used until they are worn quite short. The spring E effects another important result besides securing the cutters in or tothe head B-to wit, it by its elasticity yields or gives to a certain extentunder the force of the blows of the pick and prevents thc cutters Working loose-a result which would ensue if rigid or permanent keys or clamps Were employed, as it is a Wellkn own v fact that solid unyielding substances cannot be rmly held or secured together if subjected to blows or concussions.

I am aware that niillstone-picks have previously been constructed with adjustable cutters held by recessed heads and screw-clamps, but know of no previous instance n which the clamp has been formed of an elastic bar encircled by a strap, in which the thumbscreW or clamping-screw is threaded.

Having thus described lny invention, what I claim as new, and desire to secure by Letters Patent, is-

The head l5, having,` recesses b in the upper or outer surfaces of its lips ce, the spring,` E, strap C, provided with the screw D, or its equivalent, and the cutters F, provided with the projections h at their inner ends, all being,` combined and arranged substantially as and for the purpose set forth.

-A. S. JONES.

Vitnesses:

J. E. BUSH, I. E. SPANGLER. 

